Carbs give you a sugar rush and then everything in the body goes into processing them, slowing everything else down.
You can easily test it, eat something like a subway sandwich. Record how you feel. Now take the exact same sub, but as a salad (no bun). You'll feel markedly different.
This all, of course, depends on a ton of individual factors like insulin resistance etc.
Your example seems to be about refined and simple carbs. Those do spike blood sugar. But a better diet would include more of complex carbs where the blood sugar doesn’t spike as badly as with a diet on processed and refined (fiber-less or low fiber) foods.
